Watts Bar Nuclear Plant is in an unpaid safety “stand down” for 1,000 contract workers after finding cables had been erroneously removed from Unit 1 — the operating reactor — in December, said officials at the Tennessee Valley Authority (TVA).
In another mistake last week, a valve in Unit 2, the reactor under construction at the plant, also ended removed from another system without workers following proper guidelines.
Mike Skaggs, TVA’s senior vice president for nuclear generation, development and construction, ordered the stand-down “until the errors discovered are clearly communicated to all personnel,” along with TVA’s demand for quality work, said TVA spokeswoman Barbara Martocci.
No one was hurt and at no time was the safety of the public put at risk, she said.
“We’re taking the construction of the plant seriously as far as the health and safety of our employees,” she said. “This sort of thing is necessary when we find errors that could have been prevented and weren’t.”
Officials found the problems during normal TVA inspections, but they pile another layer of safety concerns on the utility that already faces heightened scrutiny from the Nuclear Regulatory Commission (NRC) at all three of its nuclear plants.
Last summer, NRC placed TVA’s Browns Ferry plant near Athens, AL, under a red finding, the regulator’s most serious safety flag.
In November, NRC placed Sequoyah Nuclear Plant outside Chattanooga, TN, under a white finding, the lowest safety rating, because the plant had too many unplanned reactor shutdowns in less than a year.
In December, TVA disclosed the NRC had raised another white safety flag at Watts Bar for concerns within the security division.
Under NRC’s color-coded inspection findings, white is least serious, then yellow, then red. A plant operating with no safety problems is coded green.
NRC spokesman Joey Ledbetter said the commission’s resident inspectors at Watts Bar are following up on the most-recent incidents.
Watts Bar Unit 1 reactor is the nation’s youngest, operating since 1996, and the plant’s new twin reactor, Unit 2, is still under construction. TVA has color coded the two reactors to help workers know they are working on the correct reactor.
Nonetheless, Martocci said the contractors who removed the cables from a set of backup pressurizer heaters were working on the wrong reactor.
In the second incident, the removed valve had specific instructions, and workers did not follow those instructions, she said.
Ledbetter and Martocci said the stand-down order should get the attention of the workforce.
“It gives management an opportunity to communicate the importance of a strong safety culture,” said Ledbetter.
Martocci said TVA managers had to come up with ways to talk to and train — perhaps even retrain — workers to be more mindful of safety rules and processes.